1. Field of the Invention
The present invention relates generally to the field of fluid coupling devices having separable first and second (e.g., male and female) sections, and, more particularly, to an improved automatically-operated self-sealing zero-spillage fluid coupling device in which a pair of interfitting valve elements are rotated sequentially from flow-preventing positions to flow-permitting positions upon relative movemt of one section toward the other (e.g., axially).
2. Description of the Prior Art
Fluid coupling devices are, of course, broadly known. It is also known to provide such coupling devices with a quick-disconnect mechanism to facilitate engagement and separation of the male section and the female section.
It is also known to provide such coupling devices with at least one rotary valve element that moves angularly from a flow-preventing position to a flow-permitting position upon axial insertion of one coupling section into the other, and vice versa. This type of couping device is called "self-sealing" because such valve elements automatically block the flow passage when the sections are separated from one another. Examples of such self-sealing coupling devices are shown in U.S. Pat. Nos. 4,473,211 (Fremy), 3,078,068 (Romney), 3,279,497 (Norton et al.), 4,181,149 (Cox), 2,948,553 (Gill et al.), 2,991,090 (DeCenzo), 3,382,892 (Cerbin), 3,921,656 (Meisenheimer et al.), 3,423,063 (German), 4,445,664 (Allread), 3,167,092 (Kelly et al.), 3,545,490 (Burrus) and 4,438,779 (Allread). However, in each of the foregoing references, the rotary valve elements were physically separated from one another when the male and female sections where joined together. This separation trapped a volume of fluid between the rotary valve elements, which fluid was spilled or lost when the sections were separated from one another.
It is also known to provide a "zero-spillage" coupling device. This type of device has two interfitting rotary valve elements, usually in the form of ball valves. One of the ball valves has a concave recess extending radially inwardly from its outer surface, which recess is adapted to receive a convex portin of the other ball valve when the sections are joined together. However, to establish a flow passage through the connected coupling device, it was necessary to rotate the ball valves sequentially. Specifically, that ball valve which did not have the convex recess was caused to first rotate from its flow-preventing position to its flow-permitting position, after which the ball valve with the recess could be caused to rotate to its flow-permitting position. Such interfitting ball valves, as well as the particular sequence of operation, are shown and described in U.S. Pat. Nos. 2,440,946 (Hansen), 2,376,803 (Mower et al.), 4,335,747 (Mitsumoto et al.) and 2,458,899 (Doubrava).
U.S. Pat. No. 3,159,180 (Courtot et al.) discloses a quick-disconnect fluid coupling device having separable male and female sections in combination with an interfitting "zero-spillage" rotating ball valve arrangement. However, this device required that the respective male and female coupling sections be first angularly oriented, and thereafter rotated relative to one another to effect the required sequence of valve element rotation.